U.S. patent number 6,403,069 [Application Number 09/693,248] was granted by the patent office on 2002-06-11 for high oil clear emulsion with elastomer.
This patent grant is currently assigned to Colgate-Palmolive Company. Invention is credited to Suman Chopra, Lin Fei, Eric Guenin, Jairajh Mattai, Xiaozhong Tang.
United States Patent |
6,403,069 |
Chopra , et al. |
June 11, 2002 |
**Please see images for:
( Certificate of Correction ) ** |
High oil clear emulsion with elastomer
Abstract
A clear antiperspirant and/or deodorant composition is disclosed
in the form of an emulsion having a refractive index less than 1.42
and comprising: (a) 25-70% of an external phase comprising: (i)
0.1-10%, on an actives basis, of at least one elastomer which is a
dimethicone/vinyldimethicone crosspolymer composition made by
reacting a polymethylhydrogensiloxane with an alpha,
omega-divinylpolydimethyl siloxane for which the
dimethicone/vinyl-dimethicone crosspolymer composition is used at a
concentration of 4-10% in cyclomethicone, has a refractive index in
the range of 1.392-1.402 at 25 degrees C and a viscosity in the
range of 0.013-1.times.10.sup.4 Pascal seconds; (ii) 0.1-5% of a
silicone copolyol having an HLB value .ltoreq.8; (iii) 0.1-68% of a
volatile silicone selected in an amount to complete the external
phase; (iv) 0-10% of a cosurfactant or emulsifier having an HLB
value in the range of 1-15; (v) 0-5% of a non-volatile silicone;
and (b) 30-75% of an internal phase which is made with: (i) 7-25%
(on an anhydrous actives basis (excluding the waters of hydration)
of an antiperspirant active; (ii) 0-10% ethanol; (iii) additional
water as required to adjust the refractive index; (iv) 0-5% of an
antimicrobial agent; and (v) 0-5% of an ionizable salt; wherein the
conductance of a water droplet applied to the surface of a thin
film of the antiperspirant and/or deodorant composition is at least
250 micro Siemens/cm/ml as measured by a fixed geometry test at a
loading of at least 7% by weight level of antiperspirant
active.
Inventors: |
Chopra; Suman (Dayton, NJ),
Mattai; Jairajh (Piscataway, NJ), Fei; Lin (Scotch
Plains, NJ), Guenin; Eric (Pennington, NJ), Tang;
Xiaozhong (Bridgewater, NJ) |
Assignee: |
Colgate-Palmolive Company (New
York, NY)
|
Family
ID: |
24783912 |
Appl.
No.: |
09/693,248 |
Filed: |
October 20, 2000 |
Current U.S.
Class: |
424/65; 424/400;
424/401; 424/68 |
Current CPC
Class: |
A61K
8/064 (20130101); A61K 8/585 (20130101); A61K
8/894 (20130101); A61K 8/895 (20130101); A61Q
15/00 (20130101); A61K 2800/262 (20130101) |
Current International
Class: |
A61K
8/72 (20060101); A61K 8/892 (20060101); A61K
8/04 (20060101); A61K 8/06 (20060101); A61K
007/32 (); A61K 007/38 (); A61K 007/00 () |
Field of
Search: |
;424/65,68,400,401 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
0787758 |
|
Apr 1997 |
|
EP |
|
WO 92/19221 |
|
Nov 1992 |
|
WO |
|
WO 97/44010 |
|
Nov 1997 |
|
WO |
|
WO 98/00097 |
|
Jan 1998 |
|
WO |
|
WO 98/00104 |
|
Jan 1998 |
|
WO |
|
WO 98/18438 |
|
May 1998 |
|
WO |
|
WO 98/42307 |
|
Oct 1998 |
|
WO |
|
WO 99/51192 |
|
Oct 1999 |
|
WO |
|
Primary Examiner: Dodson; Shelley A.
Attorney, Agent or Firm: Miano; Rosemary M.
Claims
We claim:
1. A clear antiperspirant and/or deodorant composition in the form
of an emulsion having a refractive index less than 1.42 and
comprising:
(a) 25-70% of an external phase comprising:
(i) 0.1-10%, on an actives basis, of at least one elastomer which
is a dimethiconelvinyldimethicone crosspolymer composition made by
reacting a polymethylhydrogensiloxane with an alpha,
omega-divinylpolydimethyl siloxane for which the
dimethicone/vinyl-dimethicone crosspolymer composition is used at a
concentration of 4-10% cyclomethicone, has a refractive index in
the range of 1.392-1.402 at 25 degrees C and a viscosity in the
range of 0.013-1.times.10.sup.4 Pascal seconds;
(ii) 0.1-5% of a silicone copolyol having an HLB value <8;
(iii) 0.1-68% of a volatile silicone selected in an amount to
complete the external phase;
(iv) 0-10% of a cosurfactant or emulsifier having an HLB value in
the range of 1-15;
(v) 0-5% of a non-volatile silicone; and
(b) 30-75% of an internal phase which is made with:
(i) 7-25% (on an anhydrous actives basis (excluding the waters of
hydration) of an antiperspirant active;
(ii) 0-10% ethanol;
(iii) additional water as required to adjust the refractive
index;
(iv) 0-5% of an antimicrobial agent; and
(v) 0-5% of an ionizable salt;
wherein (1) the conductance of a water droplet applied to the
surface of a thin film of the antiperspirant and/or deodorant
composition is at least 250 micro Siemens/cm/ml as measured by a
fixed geometry test at a loading of at least 7% by weight level of
antiperspirant active; and (2) all amounts are in percent by weight
based on the total weight of the composition.
2. A clear antiperspirant and/or deodorant composition according to
claim 1 having an oil content of 25-50%.
3. A clear antiperspirant and/or deodorant composition according to
claim 1 having an oil content of 30-45%.
4. A clear antiperspirant and/or deodorant composition according to
claim 1 having an oil content of 40-70%.
5. A clear antiperspirant and/or deodorant composition according to
claim 1 having an oil content of 30-60%.
6. A clear antiperspirant and/or deodorant composition according to
claim 1 comprising 1-5% of the elastomer in cyclomethicone.
7. A clear antiperspirant and/or deodorant composition according to
claim 1 comprising 0.1-1.0% of the silicone copolyol.
8. A clear antiperspirant and/or deodorant composition according to
claim 1 wherein the silicone copolyol is one or more dimethicone
copolyols.
9. A clear antiperspirant and/or deodorant composition according to
claim 1 comprising 0-5% of the cosurfactant or emulsifier.
10. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the cosurfactant or emulsifier is one or more
members selected from the group consisting of:
(a) sorbitan esters and ethoxylated sorbitan esters selected from
the group consisting of PEG-20 sorbitan isostearate, sorbitan
monolaurate, polysorbate-20, polysorbate-40, polysorbate-60, and
polysorbate-80;
(b) ethoxylates selected from the group consisting of Ceteth-20,
PEG-30 castor oil, PEG-40 hydrogenated castor oil, PEG-60
hydrogenated castor oil, Laureth-7, Isolaureth-6, Steareth-10,
Steareth-20, Steareth-21, Steareth-100, Ceteareth-12, Oleth-5,
Oleth-10, and Oleath-20;
(c) ethoxylated adducts selected from the group consisting of
PEG-25 stearate, glyceryl stearate and PEG-100 stearate;
(d) PEG esters selected from the group consisting of PEG-8 oleate,
PEG-8 laurate, PEG-8 dilaurate, PEG-12 dilaurate, PEG-80
diisostearate, and PEG40 stearate;
(e) propoxylates selected from the group consisting of PPG-10
butanediol, PPG-50 oleyl ether, PPG-2-ceteareth-9, PPG-3-deceth-3,
and PPG-5-ceteth-20;
(f) ethoxylated modified triglycerides selected from the group
consisting of PEG-20 corn glycerides, and PEG-12 palm kernel
glycerides;
(g) alkylphenol aromatic ethoxylates selected from the group
consisting of dinonylphenol ethoxylate with 9 moles of ethylene
oxide, octylphenol ethoxylate with 20 moles of ethylene oxide,
octylphenol ethoxylate with 40 moles of ethylene oxide; and
(h) block copolymers which are alkoxylated glycols having
ethoxylated and propoxylated segments and which are selected from
the group consisting of Poloxamer 182, Poloxamer 234, and Meroxapol
174.
11. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the volatile silicone is added in an amount of
20-58%.
12. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the volatile silicone is added in an amount of
20-50%.
13. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the volatile silicone has a boiling point
.ltoreq.250 degrees C at one atmosphere of pressure and is one or
more members of the group consisting of
(a) cyclic polydimethylsiloxanes represented by Formula III:
##STR4##
where n is an integer with a value of 3-7; and
(b) linear polydimethylsiloxanes represented by Formula IV:
##STR5##
and t is selected to obtain a viscosity of 1-200 centistokes.
14. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the non- volatile silicone has a boiling point
greater than 250 degrees at one atmosphere of pressure.
15. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the non- volatile silicone is one or more
members selected from the group consisting of phenyl trimethicone,
dimethicone, phenylpropyltrimethicone, cetyl dimethicone, and
dimethiconol.
16. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the antiperspirant active is one or more members
selected from the group consisting of aluminum salts,
aluminum/zirconium salts, aluminum/zirconium salts complexed with a
neutral amino acid.
17. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the antiperspirant active is one or more members
selected from the group consisting of aluminum chlorides, zirconyl
hydroxychlorides, zirconyl oxychlorides, basic aluminum chlorides,
basic aluminum chlorides combined with zirconyl oxychlorides and
hydroxychlorides, and organic complexes of each of basic aluminum
chlorides with or without zirconyl oxychlorides and
hydroxychlorides and mixtures of any of the foregoing.
18. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the antiperspirant active is one or more members
selected from the group consisting of aluminum chlorohydrate,
aluminum chloride, aluminum sesquichlorohydrate, aluminum
chlorohydrol-propylene glycol complex, zirconyl hydroxychloride,
alumninum-zirconium glycine complex, aluminum dichlorohydrate,
aluminum chlorohydrex PG, aluminum chlorohydrex PEG, aluminum
dichlorohydrex PG, aluminum dichlorohydrex PEG, aluminum zirconium
trichlorohydrex gly propylene glycol complex, aluminum zirconium
trichlorohydrex gly dipropylene glycol complex, aluminum zirconium
tetrachlorohydrex gly propylene glycol complex, and aluminum
zirconium tetrachlorohydrex gly dipropylene glycol complex.
19. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the antiperspirant active is added to the
composition in the form of a solution.
20. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the antiperspirant active has a metal:chloride
molar ratio in the range of 0.9-1.2:1 and a glycine: zirconium
ratio greater than 1.4:1.
21. A clear antiperspirant and/or deodorant composition according
to claim 20 wherein the antiperspirant active has a metal:chloride
molar ratio in the range of 0.9-1.1:1.
22. A clear antiperspirant and/or deodorant composition according
to claim 1 comprising an antimicrobial agent.
23. A clear antiperspirant and/or deodorant composition according
to claim 1 comprising an ionizable salt of the form M.sub.a X.sub.b
where a=1 or 2; b=1 or 2; M is a member selected from the group
consisting of Na.sup.+1, Li.sup.+1, K.sup.+1, Mg.sup.+2, Ca.sup.+2,
Sr.sup.+2, Sn.sup.+2, and Zn.sup.+2 ; and X is a member selected
from the group consisting of chloride, bromide, iodide, citrate,
gluconate, lactate, glycinate, glutamate, ascorbate, aspartate,
nitrate, phosphate, hydrogenphosphate, dihydrogenphosphate,
formate, malonate, maleate, succinate, carbonate, bicarbonate,
sulfate and hydrogensulfate.
24. A clear antiperspirant and/or deodorant composition according
to claim 1 additionally comprising 0.5-50% of an emollient.
25. A clear antiperspirant and/or deodorant composition according
to claim 24 wherein the emollient is selected from the group
consisting of
(a) fats and oils which are natural or synthetic glyceryl esters of
fatty acids having a general structure of Formula VI: ##STR6##
wherein each of R.sup.1, R.sup.2, and R.sup.3 may be the same or
different and have a carbon chain length (saturated or unsaturated)
of 7 to 30;
(b) hydrocarbons selected from the group consisting of paraffins,
petrolatum, hydrogenated polyisobutene, and mineral oil.
(c) esters of formula R.sup.4 CO--OR.sup.5 wherein the chain length
for R.sup.4 and R.sup.5 is independently selected to be in the
range of from 7 to 30, R.sup.4 and R.sup.5 and can be saturated or
unsaturated, straight chained or branched;
(d) saturated and unsaturated fatty acids having a formula R.sup.6
COOH wherein R.sup.6 has a carbon chain length from 7 to 30 and is
straight chain or branched;
(e) saturated and unsaturated fatty alcohols having a formula
R.sup.7 COH where R.sup.7 has a carbon chain length from 7 to 30
and is straight chain or branched;
(f) lanolin and its derivatives having a formula R.sup.8 CH.sub.2
--(OCH.sub.2 CH2).sub.n OH wherein R.sup.8 represents the fatty
groups derived from lanolin and n=5 to 75 or R.sup.9 CO--(OCH.sub.2
--CH.sub.2).sub.n OH where R.sup.9 CO-- represents the fatty acids
derived from lanolin and n=5 to 100;
(g) alkoxylated alcohols wherein the alcohol portion is selected
from aliphatic alcohols having 2-18 carbons, and the alkylene
portion is selected from the group consisting of ethylene oxide,
and propylene oxide having a number of alkylene oxide units from
2-53;
(h) ethers selected from the group consisting of dicaprylyl ether;
dicetyl ether; dimethyl ether; distearyl ether; ethyl ether;
isopropyl hydroxycetyl ether; methyl hexyl ether; polyvinyl methyl
ether;
(i) silicones and silanes which are members of the group consisting
of:
(1) (R.sup.10).sub.3 SiO(Si (R.sup.11).sub.2 O).sub.x
Si(R.sup.12).sub.3 where R.sup.10, R.sup.11 and R.sup.12 can be the
same or different and are each independently selected from the
group consisting of phenyl and C1-C60 alkyl;
(2) HO(R.sup.14).sub.2 SiO(Si (R.sup.15).sub.2 O).sub.x
Si(R.sup.16).sub.2 OH, where R.sup.14, R.sup.15 and R.sup.16 can be
the same or different and are each independently selected from the
group consisting of phenyl and C1-C60 alkyl; or
(3) organo substituted silicon compounds of formula R.sup.17
Si(R.sup.18)OSiR.sup.19 which are not polymeric where R.sup.17,
R.sup.18 and R.sup.19 can be the same or different and are each
independently selected from the group consisting of phenyl and
C1-C60 alkyl optionally with one or both of the terminal R groups
also containing an hydroxyl group;
(i) adipic acid blends selected from the group consisting of
trimethyl pentanediol/adipic acid copolymer; trimethyl
pentanediol/adipic acid/isononanoic acid copolymer; and adipic
acid/diethylene glycol/glycerin crosspolymer; and
(j) mixtures and blends of two or more of the foregoing.
26. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the conductance is greater than 300 micro
Siemens/cm/ml.
27. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the conductance is greater than 400 micro
Siemens/cm/ml.
28. A clear antiperspirant and/or deodorant composition according
to claim 1 wherein the conductance is greater than 500 micro
Siemens/cm/ml.
Description
FIELD OF THE INVENTION
This invention relates to clear antiperspirant and/or deodorant
products which include an antiperspirant active ingredient and
which provides better efficacy, stability and enhanced aesthetics.
The compositions are emulsions made with an external (or oil) phase
and an internal phase which contains the active ingredient. These
emulsions may be used to form clear gel, soft solid or roll-on
products.
BACKGROUND OF THE INVENTION
A large variety of antiperspirant and/or deodorant formulations
have been described in the patent literature and/or have been made
commercially available. These products have included suspension as
well as emulsions. Also various physical forms may be used such as
solids (for example, wax and sticks), semi-solids (for example,
gels and creams), liquids (for example, roll-on products) and
sprays (both aerosol and non-aerosol). In recent years a strong
emphasis has been placed on improving both the performance and the
aesthetics of these products. One of the particular problems is
trying to obtain an emulsion product that has efficacy comparable
to suspension products. A second problem is the stabilization of
emulsion products to achieve a product that is shelf stable, but
which releases an active ingredient in a timely manner.
With regard to emulsions, U.S. Pat. No. 4,673,570 to Soldati
describes uniform, clear gelled antiperspirant compositions, free
of waxes wherein the emulsions comprise in combination a volatile
silicone fluid, a silicone emulsifier (such as a mixture of
cyclomethicone and dimethicone copolyol), a destabilizing auxiliary
emulsifier, water, a non-volatile emollient (such as C10-C20 alkyl
fatty esters and ethers), linear silicone fluids, a coupling agent
(such as low molecular weight alcohols and glycols), an active
antiperspirant component and other ancillary agents.
U.S. Pat. No. 5,008,103 to Raleigh et al describes water-in-oil
antiperspirant emulsions having a discontinuous polar phase
containing water and optionally containing an emulsifier with a
hydrophilic-lipophilic balance (HLB value) greater than 8, and a
volatile silicone continuous phase with a dimethicone copolyol
emulsifier. U.S. Pat. No. 5,401,870 to Raleigh et al and U.S. Pat.
5,292,503 to Pereira et al describe similar subject matter.
U.S. Pat. No. 5,216,033 to Pereira et al describes a transparent
water-in-oil emulsion containing a silicone phase with a
dimethicone copolyol and an aqueous phase containing a refractive
index "transparency structurant" to produce a refractive index
matched clear emulsion. The transparency structurant is a C3-C8
polyhydric alcohol.
U.S. Pat. No. 5,989,531 describes a liquid composition made with
(a) an active phase comprising a selected glycol, a nonionic
emulsifier having an HLB value greater than 8 and an antiperspirant
and/or deodorant active; and (b) a silicone phase made with one or
more of a dimethicone copolyols having an HLB less than 7 and
nonionic emulsifiers having an HLB greater than 7, wherein the
silicone phase has at least 10% silicone and the ratio of the
silicone phase to the active phase is in the range of 1:1-1:4.
Optional ingredients include the use of non-volatile silicones,
volatile silicones and organic emollients.
U.S. Pat. No. 6,010,688 discloses the use of polyhydric alcohols to
improve the stability and efficacy of antiperspirant formulations,
particularly antiperspirant gels.
U.S. Pat. No. 5,955,065 discloses antiperspirant gel compositions
containing soluble calcium salts. These compositions contain an
aluminum or aluminum-zirconium antiperspirant salt and a water
soluble calcium salt, both of which are suspended in a
dermatologically acceptable anhydrous carrier vehicle. The present
invention also embraces a method of inhibiting or reducing
perspiration by topically applying an effective amount of such an
antiperspirant composition to the skin.
U.S. Pat. No. 5,925,338 discloses a clear antiperspirant or
deodorant gel composition which exhibits reduced staining while
retaining excellent aesthetic attributes and efficacy. The oil
phase comprises about 10 to 25% of the composition and contains a
silicone oil and a polyether substituted silicone emulsifying
agent. The silicone oil comprises a mixture of a non-volatile
silicone, preferably a non-volatile linear silicone, and a volatile
linear silicone. It has been found that reducing the amount of
non-volatile silicone in the known gel composition to a relatively
low level (e.g. below about 5%) and adding an amount of volatile
linear silicone to the composition (e.g. above about 2%, preferably
above about 5%) substantially improves the non-staining properties
of the composition.
U.S. Pat. No. 5,623,017 discloses a clear silicone gel cosmetic
composition with a water-containing internal phase. The silicone
emulsifiers discussed are non-polymeric ethoxylated
bis-trisiloxanes.
U.S. Pat. No. 6,007,799 discloses a clear cosmetic gel composition
in the form of a water-in-oil emulsion, comprising (a) a
water-based phase comprising water, a cosmetically active
ingredient, and at least one coupling agent; and (b) an oil-based
phase comprising a material having a refractive index in the range
of 1.40-1.50, silicone fluids and an alkoxylated, alkyl substituted
siloxane surface active agent (e.g., dimethicone copolyol). The
composition has a refractive index in a range of 1.4026 to 1.4150.
Where the cosmetically active ingredient is an antiperspirant
active ingredient, the composition can be an antiperspirant gel
(for example, soft gel) composition. In the refractive index range
of the present invention, increased amounts of, for example,
antiperspirant active ingredient, and other high-refractive-index
materials providing cosmetic benefits, can be incorporated in the
water and oil phases of the composition while still achieving a
clear composition. The composition can also include polypropylene
glycols (for example, tripropylene glycol), as part of the
water-based phase, to provide a composition having reduced
tackiness and reduced whitening (decreased residue); this
composition is also mild.
U.S. Pat. No. 5,587,173 discloses a clear gel-type cosmetic product
which has a viscosity of at least about 50,000 centipoise (cps) at
21.degree. C., and includes an emulsion with an oil phase and a
water phase that includes an incorporated active ingredient. The
refractive indices of the water and oil phases match to at least
0.0004, the refractive index of the product is about 1.4000, and
the product clarity is better than thirty NTU. These formulas
contain 75-90% dispersed active phase. See also U.S. Pat. No.
4,021,536: which describes magnesium-zirconium complexes useful as
antiperspirants; and U.S. Pat. No. 5,463,098 which describes clear
antiperspirant gel stick and method for making same.
U.S. Pat. No. 3,979,510 describes aluminum-zirconium antiperspirant
systems with complex aluminum buffers, including the use of various
divalent metal ions in aluminum-zirconium antiperspirant
formulations.
U.S. Pat. No. 4,980,156 discloses improved dry-feeling
antiperspirant compositions which comprise an aqueous solution of
an astringent emulsified in a volatile silicon fluid. The emulsion
is stabilized by using a combination of a long-chain alkyl modified
polysiloxane-polyoxyalkylene copolymer and an organic surfactant
having an HLB value from 8 to 18.
U.S. Pat. No. 4,673,570 discloses uniform, clear gelled
antiperspirant compositions, free of waxes and conventional gelling
agents. The gel emulsions comprise, in combination, a volatile
silicone fluid, a silicone emulsifier, a destabilizing auxiliary
emulsifier, water, a non-volatile emollient, a coupling agent, an
active antiperspirant component and ancillary agents.
U.S. Pat. No. 5,454,026 discloses a clear antiperspirant gel which
is made by combining (a) an astringent compound having a refractive
index of 1.48 to 1.53 which is an antiperspirant salt in the form
of (i) a tray dried compound, (ii) an encapsulated salt, or (iii) a
solvent solution of a salt compound; and (b) a clear anhydrous
organic oil-free gel formed with 12-hydroxystearic acid as the
gelling agent and a blend of aromatic containing silicone fluid and
volatile silicone fluids.
U.S. Pat. No. 5,587,153 broadly discloses clear antiperspirant gels
with a refractive index of 1.3975 to 1.4025 and a viscosity of
50,000-200,000 centipoise which are emulsions having 75-90% of a
water phase.
U.S. Pat. No. 5,563,525 also discloses clear antiperspirant gels
having a viscosity of at least 50,000 centipoise and a clarity
better than 50 NTU which are emulsions having 75-90% of a water
phase.
U.S. Pat. No. 6,060,546 to Powell et al describes a non-aqueous
silicone emulsion containing a silicone phase and an organic phase
in which the silicone phase contains a crosslinked silicone
elastomer and the organic phase may contain up to 50% water.
U.S. Pat. No. 6,103,250 describes an anhydrous composition
comprising 1-50% of a polar, emulsifying siloxane elastomer,
0.01-40% particulate material, and 1-70% of a nonpolar oil, wherein
the elastomer is present in an amount to render the incompatible
nonaqueous polar ingredient compatible in the anhydrous
composition.
U.S. Pat. No. 5,922,308 to Brewster et al describes an underarm
composition comprising 0.1-5.5% of a crosslinked non-emulsifying
siloxane elastomer and 10-80% of volatile siloxane.
Historically, suspension products such as sticks have exhibited
better efficacy than emulsion products. Previous attempts have not
successfully overcome the problems of improving efficacy and
achieving satisfactory formation of emulsions.
As an additional aspect of the invention, it has heretofore been
difficult to obtain a clear emulsion when an elastomer was present.
Also, it was been very difficult to get the elastomer to mix
satisfactorily in an emulsion environment and the elastomer
particles tend to still remain as isolated particles.
Examples of elastomer compositions include the following. PCT case
WO 97/44010 and assigned to the same assignee as this application
describes a silicone gel material made by combining (a) a volatile
silicone material and (b) an organopolysiloxane material (or
silicone elastomer) as a gelling agent wherein the
organopolysiloxane material (silicone elastomer) can be a reaction
product of a vinyl-terminated siloxane polymer and a silicon
hydride cross-linking agent. Related technology is also disclosed
in PCT case WO 98/00097, WO 98/00104 and 98/00105 assigned to
Unilever PLC on cross-linked non-emulsifying elastomers.
U.S. Pat. No. 5,599,533 to Stepniewski et al assigned to Estee
Lauder describes a stable water-in-oil emulsion system formed with
an organopolysiloxane elastomer, a vehicle in which the elastomer
is dispersed or dispersible, a stabilizing agent, a surfactant and
an aqueous component. A commercial product known as "REVELATION"
retexturizing complex for hands and chest sold by the same assignee
contains a silicone gel material with an organopolysiloxane
component and octamethylcyclotetrasiloxane. This reference does not
teach a clear composition and also teaches that you have to cap the
electrolyte at 5%. In addition, this reference relies on polyols
and alcohols as stabilizing agents.
EP 0 787 758 A1 teaches a method for solvent thickening by using a
silicone latex having a plurality of crosslinked polysiloxane
particles.
Another recent case assigned to the same assignee as this
application is WO 99/51192 and U.S. patent application Ser. No.
9/273152 which describes antiperspirant compositions with the use
of broad categories of elastomers. Other examples of the use of
elastomer type materials and/ or methods for processing such
materials may be found in PCT cases WO 98100097; WO 98/00104; WO
98/00105; WO 98/18438; WO 98142307 all of which are incorporated
herein by reference.
Thus, it is an object of this invention to provide improved
emulsions containing 25%-70% of an oil phase which exhibit improved
efficacy which efficacy is comparable to that achieved in
suspension products and, at the same time, have a stability profile
that allows for satisfactory stability on the shelf. Another issue
is the formation of emulsions which are stable on the shelf but
which destabilize sufficiently after application to a skin surface
so as to release an efficacious amount of an active ingredient.
Thus, it is an object of the present invention to provide emulsions
with those characteristics as well as enhanced aesthetics such as
smoothness in application, low tack and dry feel. It is also an
object of this invention to provide gel or soft solid compositions
which can, if desired, be formed into clear compositions even with
the presence of selected elastomer materials. It is still another
object of this invention to provide compositions that can, if
desired, be formed into clear compositions without the use of
microemulsions.
SUMMARY OF THE INVENTION
This invention relates to a clear antiperspirant and/or deodorant
composition in the form of a water-in-oil emulsion having a
refractive index less than 1.42 and comprising:
(a) 25-70% (particularly with a high oil content of 25-50%, and
more particularly 30-45%) of an external phase (also called the oil
phase or the continuous phase) which is made with:
(i) 0.1-10% (on an actives basis) of at least one elastomer which
is a dimethicone/vinyldimethicone crosspolymer composition made by
reacting (in the presence of a platinum catalyst) a
polymethylhydrogensiloxane with an alpha, omega-divinylpolydimethyl
siloxane for which the dimethicone/vinyl-dimethicone crosspolymer
composition is used at a concentration of 4-10%, (especially 4-6%)
in cyclomethicone (for example a D4 or D5 cyclomethicone), has a
refractive index in the range of 1.392-1.402 at 25 degrees C and a
viscosity in the range of 0.013-1.times.10.sup.4 Pascal
seconds;
(ii) 0.1-5% (particularly 0.1-1.0%) of a silicone copolyol having
an HLB value (hydrophilic lipophilic balance).ltoreq.8;
(iii) 0.1-68% of a volatile silicone selected in an amount to
complete the external phase;
(iv) 0-10% particularly 0-5%) of a cosurfactant or emulsifier
having an HLB value in the range of 1-15;
(v) 0-5% of a non-volatile silicone; and
(b) 30-75% (particularly 50-75%) of an internal phase (also called
actives phase or dispersed phase) which is made with:
(i) 7-25% (on an anhydrous actives basis and excluding the waters
of hydration) of an antiperspirant active preferably added as a
solution of active in water and/or water+glycol mixture as a
solvent;
(ii) 0-10% ethanol;
(iii) additional water as needed to adjust the refractive
index;
(iv) 0-5% of an antimicrobial agent; and
(v) 0-5% of an ionizable salt;
wherein (1) the conductance of a water droplet applied to the
surface of a thin film of the antiperspirant and/or deodorant
composition is at least 250 micro Siemens/cm/ml as measured by the
fixed geometry test described below at a loading of at least 7% by
weight level of antiperspirant active (with more particular
embodiments having conductances greater than 300 micro
Siemens/cm/ml, particularly greater than 400 micro Siemens/cm/ml
and especially greater than 500 micro Siemens/cm/ml.); and (2) all
amounts are in percent by weight based on the total weight of the
composition unless otherwise specified.
DETAILED DESCRIPTION OF THE INVENTION
The clear cosmetic compositions of this invention having a
refractive index less than 1.42 are made with 25-70 (particularly
25-50% and, more particularly, 30-45%) of an external phase and
30-75% (particularly 50-75% and, more particularly, 55-70%) of an
internal phase. Alternatively, another specific embodiment can
include 40-70% and more particularly 50-60% of an external phase;
and 30-60% and more particularly 40-50% of an internal phase.
The elastomer component described above is used in an amount of
0.1-10% (on an actives basis) particularly in an amount of 1-7%
and, more particularly, in an amount of 1-5%. One particular
elastomer of interest is KSG-15 silicone elastomer from Shin-Etsu
Silicones of America (Akron, Ohio). Frequently the elastomer is
obtained as a mixture in cyclomethicone.
A silicone copolyol (especially dimethicone copolyol) may be used
in an amount of 0.1-5% (actives basis), particularly 0.1-3% and,
more particularly, 0.1-1.0%.
In general, silicone copolyols useful in the present invention
include copolyols of the following Formulae I and II. Formula I
materials may be represented by:
wherein each of R.sup.10, R.sup.11, R.sup.12 and R.sup.13 may be
the same or different and each is selected from the group
consisting of C1-C6 alkyl; R.sup.b is the radical --C.sub.m
H.sub.2m --; R.sup.c is a terminating radical which can be
hydrogen, an alkyl group of one to six carbon atoms, an ester group
such as acyl, or an aryl group such as phenyl; m has a value of two
to eight; p and s have values such that the oxyalkylene segment
--(C.sub.2 H.sub.4 O).sub.p --(C.sub.3 H.sub.6 O).sub.s --of has a
molecular weight in the range of 200 to 5,000; the segment
preferably having fifty to one hundred mole percent of oxyethylene
units --(C.sub.2 H.sub.4 O).sub.p -- and one to fifty mole percent
of oxypropylene units --(C.sub.3 H.sub.6 O).sub.s --; x has a value
of 8 to 400; and y has a value of 2 to 40. Preferably each of
R.sup.10, R.sup.11, R.sup.12 and R.sup.13 is a methyl group;
R.sup.c is H; m is preferably three or four whereby the group
R.sup.b is most preferably the radical --(CH.sub.2).sub.3 --; and
the values of p and s are such as to provide a molecular weight of
the oxyalkylene segment --(C.sub.2 H.sub.4 O)p--(C.sub.3 H.sub.6
O).sub.s -- of between about 1,000 to 3,000. Most preferably p and
s should each have a value of about 18 to 28.
A second siloxane polyether (copolyol) has the Formula II:
wherein p has a value of 6 to 16; x has a value of 6 to 100; and y
has a value of 1 to 20 and the other moieties have the same
definition as defined in Formula I.
It should be understood that in both Formulas I and II shown above,
that the siloxane-oxyalkylene copolymers of the present invention
may, in alternate embodiments, take the form of endblocked
polyethers in which the linking group R.sup.b, the oxyalkylene
segments, and the terminating radical R.sup.c occupy positions
bonded to the ends of the siloxane chain, rather than being bonded
to a silicon atom in the siloxane chain. Thus, one or more of the
R.sup.10, R.sup.11, R.sup.12 and R.sup.13 substituents which are
attached to the two terminal silicon atoms at the end of the
siloxane chain can be substituted with the segment --R.sup.b
--O--(C.sub.2 H.sub.4 O).sub.p --(C.sub.3 H.sub.6 O).sub.s
--R.sup.c or with the segment --R.sup.b --O--(C.sub.2 H.sub.4
O).sub.p --R.sup.c. In some instances, it may be desirable to
provide the segment --R.sup.b --O--(C.sub.2 H.sub.4 O).sub.p
--(C.sub.3 H.sub.6 O).sub.s --R.sup.c or the segment --R.sup.b
--O--(C.sub.2 H.sub.4 O).sub.p --R.sup.c at locations which are in
the siloxane chain as well as at locations at one or both of the
siloxane chain ends.
Particular examples of suitable dimethicone copolyols are available
either commercially or experimentally from a variety of suppliers
including Dow Coming Corporation, Midland, Mich.; General Electric
Company, Waterford, N.Y.; Witco Corp., Greenwich, Conn.; and
Goldschmidt Chemical Corporation, Hopewell, Va. Examples of
specific products include DOW CORNING.RTM. 5225C from Dow Coming
which is a 10% dimethicone copolyol in cyclomethicone; DOW
CORNING.RTM. 2-5185C which is a 45-49% dimethicone copolyol in
cyclomethicone; SILWET L-7622 from Witco; ABIL EM97 from
Goldschmidt which is a 85% dimethicone copolyol in D5
cyclomethicone; and various dimethicone copolyols available either
commercially or in the literature.
It should also be noted that various concentrations of the
dimethicone copolyols in cyclomethicone can be used. While a
concentration of 10% in cyclomethicone is frequently seen
commercially, other concentrations can be made by stripping off the
cyclomethicone or adding additional cyclomethicone. The higher
concentration materials such as DOW CORNING.RTM. 2-5185 material is
of particular interest.
In one particular embodiment 0.1-5% (particularly 1.0-5.0%) of a
10-50% silicone copolyol such as dimethicone copolyol in
cyclomethicone mixture may be used, wherein the amount of mixture
added is selected so that the level of silicone copolyol in the
cosmetic composition is in the range of 0.25-5.0% (particularly 1%)
(for example, 0.25-10% of a 40%-50% dimethicone copolyol in
cyclomethicone mixture).
For the volatile silicone component, an amount of 0.1-68% may be
used plus an incremental amount to complete the selected amount of
the external phase (quantum sufficient or "q.s."). Particular
ranges include an amount in the range of 10-58%, (more particularly
10-50% and, even more particularly, 15-30%) by weight based on the
entire weight of the composition should be used. By volatile
silicone material is meant a material that has a measurable vapor
pressure at ambient temperature. For the volatile silicone portion,
examples of volatile silicones (particularly silicones with a
boiling point of 250 degrees C or less at atmospheric pressure)
include cyclomethicone (especially cyclopentasiloxane, also called
"D5"), "hexamethyldisiloxane", and low viscosity dimethicone (for
example, Dow Coming.RTM. 200 fluid having a viscosity of 1-200
centistokes). Such volatile silicones include conventional cyclic
and linear volatile silicones Illustratively, and not by way of
limitation, the volatile silicones are one or more members selected
from the group consisting of cyclic polydimethylsiloxanes such as
those represented by Formula III: ##STR1##
where n is an integer with a value of 3-7, particularly 5-6. For
example, DC-245 fluid (or the DC-345 version) from Dow Coming
Corporation (Midland, Mich.) is a type of cyclomethicone which can
be used. These include a tetramer (or
octylmethylcyclotetrasiloxane) and a pentamer (or
decamethylcyclopentasiloxane). The volatile linear silicones can
also be included in this group of volatile silicones and are one or
more members selected from the group consisting of linear
polydimethylsiloxanes such as those represented by Formula IV:
##STR2##
and t is selected to obtain a viscosity of 1-200 centistokes.
The co-surfactants used in this invention (which can also be a
mixture or blend of surfactants) include, but are not limited to at
least one member selected from the group consisting of:
(a) sorbitan esters and ethoxylated sorbitan esters (for example
PEG-20 sorbitan isostearate, sorbitan monolaurate, polysorbate-20,
polysorbate-40, polysorbate-60, polysorbate-80);
(b) ethoxylates (for example, Ceteth-20, PEG-30 castor oil, PEG-40
hydrogenated castor oil, PEG-60 hydrogenated castor oil, Laureth-7,
Isolaureth-6, Steareth-10, Steareth-20, Steareth-21, Steareth-100,
Ceteareth-12, Oleth-5, Oleth-10, and Oleath-20);
(c) ethoxylated adducts (for example, PEG-25 stearate, glyceryl
stearate and PEG-100 stearate);
(d) PEG esters (for example, PEG-8 oleate, PEG-8 laurate, PEG-8
dilaurate, PEG-12 dilaurate, PEG-80 diisostearate, PEG-40
stearate);
(e) propoxylates (for example, PPG-10 butanediol, PPG-50 oleyl
ether, PPG-2-ceteareth-9, PPG-3-deceth-3, PPG-5-ceteth-20);
(f) ethoxylated modified triglycerides (for example, PEG-20 corn
glycerides, PEG-12 palm kernel glycerides);
(g) alkylphenol aromatic ethoxylates (for example, dinonylphenol
ethoxylate with 9 moles of EO, octylphenol ethoxylate with 20 moles
of EO, octylphenol ethoxylate with 40 moles of EO); and
(h) block copolymers which are alkoxylated glycols having
ethoxylated and propoxylated segments (for example, Poloxamers 182
and 234, and Meroxapol 174);
wherein the nonionic surfactant is selected so that it has an HLB
(hydrophilic-lipophilic balance) value in the range of 1-15. The
HLB parameter is a well known parameter the calculation of which is
disclosed and explained in numerous references. For nonionic
surfactants, data obtained by actual analysis is usually a more
accurate measure of HLB values (rather than theoretical
determinations). For purposes of this invention it is intended that
either the actual or theoretical HLB value may be used as the basis
for selection.
For the co-surfactant having an HLB value .ltoreq.8, examples
include:
(a) ethoxylated alcohols such as steareth-2, Oleth-3, nonoxynol-2,
PPG-4-Ceteth-1;
(b) ethoxylated carboxylic acids such as PEG-4 dilaurate, PEG-2
oleate;
(c) glyceryl esters such as PEG-2 castor oil, PEG-7 hydrogenated
castor oil, glyceryl monooleate, glyceryl monostearate, triglycerol
monooleate, decaglyceryl tetraoleate, and polyglyceryl-3 oleate,
glyceryl stearate;
(d) sorbitan derivatives such as sorbitan oleate, sorbitan
monostearate, sorbitan tristearate, sorbitan monooleate, sorbitol
trioleate, sorbitan monotallate, sorbitan isostearate;
(e) sugar esters such as sucrose distearate; and
(f) lanolin alcohol.
The surfactant or blend of surfactants incorporated into the
compositions of the present invention can, illustratively, be
included in amounts of 0.1-20%, preferably 0.5-10%, and more
preferably 1-5%, by weight based on the total weight of the
composition.
The non-volatile silicone component may be used as an optional
emollient or to match the refractive index. Examples of
non-volatile silicones (that is, silicones with a boiling point
above 250 degrees C at atmospheric pressure) include phenyl
trimethicone, dimethicone, phenylpropyltrimethicone (SF1555 from
General Electric, Waterford, N.Y.), cetyl dimethicone, and
dimethiconol as well as two or more of the forgoing.
For the antiperspirant active used in the internal (also called
"active") phase various antiperspirant active materials that can be
utilized according to the present invention provided that they are
soluble at a suitable concentration in the active phase. These
include conventional aluminum and aluminum/zirconium salts, as well
as aluminum/zirconium salts complexed with a neutral amino acid
such as glycine, as known in the art. See each of European Patent
Application Number. 512,770 A1 and PCT case WO 92/19221, the
contents of each of which are incorporated herein by reference in
their entirety, for disclosure of antiperspirant active materials.
The antiperspirant active materials disclosed therein, including
the acidic antiperspirant materials, can be incorporated in the
compositions of the present invention if they are soluble in the
active phase. Suitable materials include (but are not limited to)
aluminum chlorides (various types including, for example, anhydrous
form, hydrated form, etc.), zirconyl hydroxychlorides, zirconyl
oxychlorides, basic aluminum chlorides, basic aluminum chlorides
combined with zirconyl oxychlorides and hydroxychlorides, and
organic complexes of each of basic aluminum chlorides with or
without zirconyl oxychlorides and hydroxychlorides and mixtures of
any of the foregoing. These include, by way of example (and not of
a limiting nature), aluminum chlorohydrate, aluminum chloride,
aluminum sesquichlorohydrate, aluminum chlorohydrol-propylene
glycol complex, zirconyl hydroxychloride, aluminum-zirconium
glycine complex (for example, aluminum zirconium trichlorohydrex
gly, aluminum zirconium pentachlorohydrex gly, aluminum zirconium
tetrachlorohydrex gly and aluminum zirconium octochlorohydrex gly),
aluminum dichlorohydrate, aluminum chlorohydrex PG, aluminum
chlorohydrex PEG, aluminum dichlorohydrex PG, aluminum
dichlorohydrex PEG, aluminum zirconium trichlorohydrex gly
propylene glycol complex, aluminum zirconium trichlorohydrex gly
dipropylene glycol complex, aluminum zirconium tetrachlorohydrex
gly propylene glycol complex, aluminum zirconium tetrachlorohydrex
gly dipropylene glycol complex, and mixtures of any of the
foregoing. The aluminum-containing materials can be commonly
referred to as antiperspirant active aluminum salts. Generally, the
foregoing metal antiperspirant active materials are antiperspirant
active metal salts. In the embodiments which are antiperspirant
compositions according to the present invention, such compositions
need not include aluminum-containing metal salts, and can include
other antiperspirant active materials, including other
antiperspirant active metal salts. Generally, Category I active
antiperspirant ingredients listed in the Food and Drug
Administration's Monograph on antiperspirant drugs for
over-the-counter human use can be used. In addition, any new drug,
not listed in the Monograph, such as tin or titanium salts used
alone or in combination with aluminum compounds (for example,
aluminum-stannous chlorohydrates), aluminum nitratohydrate and its
combination with zirconyl hydroxychlorides and nitrates, can be
incorporated as an antiperspirant active ingredient in
antiperspirant compositions according to the present invention.
Preferred antiperspirant actives that can be incorporated in the
compositions of the present invention include the enhanced efficacy
aluminum salts and the enhanced efficacy aluminurn/ zirconium
salt-glycine materials, having enhanced efficacy due to improved
molecular distribution, known in the art and discussed, for
example, in PCT No. WO92/19221, the contents of which are
incorporated by reference in their entirety herein. Particular
actives include Westchlor A2Z 4105 aluminum zirconium
tetrachlorohydrex gly propylene glycol complex, (from Westwood
Chemical Corporation, Middletown, N.Y.); Westchlor ZR 35B aluminum
zirconium tetrachlorhydrex gly, and Rezal 36 GP and AZP 902
aluminum zirconium tetrachlorhydrex gly both from Reheis, Berkeley
Heights, N.J. as well as Rezal AZZ 908 from Reheis. In general, the
metal:chloride mole ratio is in the range of 2.1-0.9:1 for such
salts.
Actives of special interest because they form low RI solutions
include: Westchlor Zr 35BX3 (30-35% actives in water) from Westwood
Chemical Company, Middletown, N.Y.; Rezal 36G (46% in water) from
Reheis Inc., Berkeley Heights, N.J.; Summit AZG-368 (28-32% in
water) from Summit Research Labs, Huguenot, N.Y.; Reach 301 (39% in
water) from Reheis Inc.; and aluminum chloride (28% in water) which
may be obtained from several sources. In general, the
metal:chloride mole ratio is approximately 1.4:1 for such
salts.
In one particular type of salt of interest, an aluminum zirconium
tetra salt with glycine is used wherein aluminum zirconium
tetrachlorohydrex glycine salt having a metal to chloride ratio in
the range of 0.9-1.2:1 (especially in the range of 0.9-1.1:1 and,
more particularly in the range of 0.9-1.0:1); and a
glycine:zirconium mole ratio greater than 1.3:1, particularly
greater than 1.4:1. This type of salt may be made in a variety of
ways as described in a co-pending case IR 6558 filed on the same
day as this case.
Method A: An aluminum chlorohydrate (ACH) solution of ACH salt in
water of suitable concentration is mixed with an aqueous solution
of zirconyl chloride (ZrOCl.sub.2) of suitable concentration and
powdered glycine. The mixture is stirred at room temperature to
obtain the salt.
Method B: A suitable commercially available aluminum zirconium
tetrachlorohydrex glycine salt is obtained and mixed with a
sufficient amount of an aqueous aluminum chloride (AlCl.sub.3)
solution and powdered glycine. The mixture is stirred at room
temperature to obtain the salt. When Method B is used, a suitable
salt to use as a starting material includes various types of tetra
salts such as aluminum zirconium tetrachlorohydrex gly, aluminum
zirconium tetrachlorohydrex gly propylene glycol complex, aluminum
zirconium tetrachlorohydrex gly dipropylene glycol complex, and
mixtures of any of the foregoing. These salts will be referred to
hereinafter as experimental salts or carry an "exp" suffix in their
designation. It is preferred that the experimental salt be used in
the form of a 28-50% water solution when added to form the
compositions of the invention.
Method C: An aqueous aluminum chlorohydrate (ACH) solution made
from an activated ACH salt of suitable concentration is mixed with
an aqueous solution of zirconyl chloride (ZrOCl.sub.2) of suitable
concentration and powdered glycine. The mixture is stirred at room
temperature for a short period of time and then spray dried to
obtain the salt in powder form.
Mixtures of actives can also be used, provided a suitable amount of
low RI material is used to achieve a satisfactory product.
Antiperspirant actives can be incorporated into compositions
according to the present invention in amounts in the range of 7-25%
(on an anhydrous solids basis), preferably 7-20%, by weight, of the
total weight of the composition. The amount used will depend on the
formulation of the composition. At amounts at the higher end of the
range (especially in a range of 9-20% or 9-25%, a good
antiperspirant effect can be expected. As noted above, the active
is preferably included in the compositions of the invention by
premixing the active with water and possibly small amount of
propylene glycol.
Deodorant active materials can also be included such as:
(a) fragrances, such as in the range of 0.5-3.0 percent by weight
based on the total weight of the composition;
(b) effective amounts of antimicrobial agents, for example,
0.05-5.0 percent (particularly 0.1-1% and, more particularly,
0.25-1.0%) by weight based on the total weight of the composition;
examples include bacteriostatic quaternary ammonium compounds (such
as cetyl trimethyl-ammonium bromide, and cetyl pyridinium
chloride), 2, 4, 4'-trichloro-2'-hydroxydiphenylether (Triclosan),
N-(4-chlorophenyl)-N'-(3,4-dichlorophenyl)urea (Triclocarban),
silver halides, octoxyglycerin (SENSIVA.TM. SC 50) and various zinc
salts (for example, zinc ricinoleate). Triclosan or Triclocarban
can, illustratively, be included in an amount of from 0.05% to
about 0.5% by weight, of the total weight of the composition;
or
(c) effective amounts of a masking agent, such as 0.1-5%.
While it has been described that the water component of the
invention may also contain a minor amount of a glycol component
such as propylene glycol, it is preferred that no added glycol be
used. The glycol component, if included, is comprised of one or
more glycols and/or a polyglycols selected from the group
consisting of ethylene glycol, propylene glycol, 1,2-propanediol,
diethylene glycol, triethylene glycol, tetraethylene glycol,
dipropylene glycol, tripropylene glycol, methyl propanediol,
1,6-hexanediol, 1,3-butanediol, 1,4-butanediol, PEG-4 through
PEG-100, PPG-9 through PPG-34, pentylene glycol, neopentyl glycol,
trimethylpropanediol, 1,4-cyclohexanedimethanol,
2,2-dimethyl-1,3-propanediol,
2,2,4,4-tetramethyl-1,3-cyclobutanediol, and mixtures thereof. More
particular examples of the glycol component include one or more
members of the group consisting of propylene glycol, dipropylene
glycol, tripropylene glycol, 2-methyl-1,3-propanediol, methyl
propylene glycol, low molecular weight (less than 600) polyethylene
glycol, low molecular weight (less than 600) polypropylene glycols,
and mixtures of any of the foregoing. Propylene glycol is of
particular interest because the antiperspirant active is more
soluble in this type of glycol. Tripropylene glycol has lower
irritancy, but the antiperspirant active is not as soluble in this
glycol. Methyl propylene glycol is also of interest. Mixtures of
glycols may be used to balance these desirable properties.
The compositions of the present invention can also include other
optional ingredients to improve the aesthetics and/or performance
of the cosmetic compositions of the invention. These include
emollients, thickeners, colorants, fillers, fragrances, masking
agents, etc.
Emollients are a known class of materials in this art, imparting a
soothing effect to the skin. These are ingredients which help to
maintain the soft, smooth, and pliable appearance of the skin.
Emollients are also known to reduce whitening on the skin and/or
improve aesthetics. Examples of chemical classes from which
suitable emollients can be found include:
(a) fats and oils which are the glyceryl esters of fatty acids, or
triglycerides, normally found in animal and plant tissues,
including those which have been hydrogenated to reduce or eliminate
unsaturation. Also included are synthetically prepared esters of
glycerin and fatty acids. Isolated and purified fatty acids can be
esterified with glycerin to yield mono-, di-, and triglycerides.
These are relatively pure fats which differ only slightly from the
fats and oils found in nature. The general structure may be
represented by Formula VI: ##STR3##
wherein each of R.sup.1, R.sup.2, and R.sup.3 may be the same or
different and have a carbon chain length (saturated or unsaturated)
of 7 to 30. Specific examples include peanut oil, sesame oil,
avocado oil, coconut, cocoa butter, almond oil, safflower oil, corn
oil, cotton seed oil, castor oil, hydrogenated castor oil, olive
oil, jojoba oil, cod liver oil, palm oil, soybean oil, wheat germ
oil, linseed oil, and sunflower seed oil;
(b) hydrocarbons which are a group of compounds containing only
carbon and hydrogen. These are derived from petrochemicals. Their
structures can vary widely and include aliphatic, alicyclic and
aromatic compounds. Specific examples include paraffin, petrolatum,
hydrogenated polyisobutene, and mineral oil.
(c) esters which chemically, are the covalent compounds formed
between acids and alcohols. Esters can be formed from almost all
acids (carboxylic and inorganic) and any alcohol. Esters here are
derived from carboxylic acids and an alcohol. The general structure
would be R.sup.4 CO--OR.sup.5. The chain length for R.sup.4 and
R.sup.5 can vary from 7 to 30 and can be saturated or unsaturated,
straight chained or branched. Specific examples include isopropyl
myristate, isopropyl palmitate, isopropyl stearate, isopropyl
isostearate, butyl stearate, octyl stearate, hexyl laurate, cetyl
stearate, diisopropyl adipate, isodecyl oleate, diisopropyl
sebacate, isostearyl lactate, C.sub.12-15 alkyl benzoates, myreth-3
myristate, dioctyl malate, neopentyl glycol diheptanoate,
dipropylene glycol dibenzoate, C.sub.12-15 alcohols lactate,
isohexyl decanoate, isohexyl caprate, diethylene glycol
dioctanoate, octyl isononanoate, isodecyl octanoate, diethylene
glycol diisononanoate, isononyl isononanoate, isostearyl
isostearate, behenyl behenate, C.sub.12-15 alkyl fumarate,
laureth-2 benzoate, propylene glycol isoceteth-3 acetate, propylene
glycol ceteth-3 acetate, octyldodecyl myristate, cetyl ricinoleate,
myristyl myristate.
(d) saturated and unsaturated fatty acids which are the carboxylic
acids obtained by hydrolysis of animal or vegetable fats and oils.
These have general structure R.sup.6 COOH with the R.sup.6 group
having a carbon chain length between 7 and 30 , straight chain or
branched. Specific examples include lauric, myristic, palmitic,
stearic, oleic, linoleic and behenic acid.
(e) saturated and unsaturated fatty alcohols (including guerbet
alcohols) with general structure R.sup.7 COH where R.sup.7 can be
straight or branched and have carbon length of 7 to 30. Specific
examples include lauryl, myristyl, cetyl, isocetyl, stearyl,
isostearyl, oleyl, ricinoleyl and erucyl alcohol;
(f) lanolin and its derivatives which are a complex esterified
mixture of high molecular weight esters of (hydroxylated) fatty
acids with aliphatic and alicyclic alcohols and sterols. General
structures would include R.sup.8 CH.sub.2 --(OCH.sub.2
CH.sub.2).sub.n OH where R.sup.8 represents the fatty groups
derived from lanolin and n=5 to 75 or R.sup.9 CO--(OCH.sub.2
CH.sub.2).sub.n OH where R.sup.9 CO-- represents the fatty acids
derived from lanolin and n=5 to 100. Specific examples include
lanolin, lanolin oil, lanolin wax, lanolin alcohols, lanolin fatty
acids, isopropyl lanolate, ethoxylated lanolin and acetylated
lanolin alcohols.
(g) alkoxylated alcohols wherein the alcohol portion is selected
from aliphatic alcohols having 2-18 and more particularly 4-18
carbons, and the alkylene portion is selected from the group
consisting of ethylene oxide, and propylene oxide having a number
of alkylene oxide units from 2-53 and, more particularly, from
2-15. Examples include cetyl glyceryl ether; isostearyl glyceryl
ether; isostearyl glyceryl pentaerythrityl ether; laureth-5 butyl
ether; oleyl glyceryl ether; PEG-4 ditallow ether; polyglyceryl-3
cetyl ether; polyglyceryl-4 lauryl ether; PPG-9 diglyceryl ether;
propylene glycol myristyl ether. More specific examples include
PPG-14 butyl ether, PPG-53 butyl ether laureth-5 butyl ether and
PEG-4 ditallow ether.
(h) ethers selected from the group consisting of dicaprylyl ether;
dicetyl ether; dimethyl ether; distearyl ether; ethyl ether;
isopropyl hydroxycetyl ether; methyl hexyl ether; polyvinyl methyl
ether;
(i) silicones and silanes the linear organo-substituted
polysiloxanes which are polymers of silicon/oxygen with general
structure:
(1) (R.sup.10).sub.3 SiO(Si (R.sup.11).sub.2 O).sub.x Si(R.sup.12)
.sub.3 where R.sup.10, R.sup.11 and R.sup.12 can be the same or
different and are each independently selected from the group
consisting of phenyl and C1-C60 alkyl;
(2) HO(R.sup.14).sub.2 SiO(Si (R.sup.15).sub.2 O).sub.x
Si(R.sup.16).sub.2 OH, where R.sup.14, R.sup.15 and R.sup.16 can be
the same or different and are each independently selected from the
group consisting of phenyl and C1-C60 alkyl; or
(3) organo substituted silicon compounds of formula R.sup.17
Si(R.sup.18)OSiR.sup.19 which are not polymeric where R.sup.17,
R.sup.13 and R.sup.19 can be the same or different and are each
independently selected from the group consisting of phenyl and
C1-C60 alkyl optionally with one or both of the terminal R groups
also containing an hydroxyl group. Specific examples include
dimethicone, dimethiconol behenate, C.sub.30-45 alkyl methicone,
stearoxytrimethylsilane, phenyl trimethicone and stearyl
dimethicone.
(j) adipic acid blends selected from the group consisting of
trimethyl pentanediol/adipic acid copolymer (LEXOREZ TL8 from
Inolex, Philadelphia, Pa.); trimethyl pentanediol/adipic
acidlisononanoic acid copolymer (LEXOREZ TC8); and adipic
acid/diethylene glycol/glycerin crosspolymer (LEXOREZ 100);
(k) mixtures and blends of two or more of the foregoing.
Particular examples of suitable emollients include members of the
group consisting of Octyloxyglyderin (SENSIVA SC50 from Schuilke
Mayr, Norderstedt, Germany) (which can be used as an emollient as
well as an antibacterial); Polysorbate 80 (TWEEN 80 from ICI
Americas, Wilmington, Del.); Oleth-20; ethoxylated alcohols such as
steareth-2, nonoxynol-2, PPG-4-Ceteth-1; ethoxylated carboxylic
acids such as PEG-4 dilaurate, PEG-2 oleate; glyceryl esters such
as PEG-2 castor oil, polyglyceryl-3 oleate, glyceryl stearate;
sorbitan derivatives such as sorbitan oleate; PPG-3 myristyl ether
(such as WITCONOL APM from Goldschmidt), a dimethiconol (such as
Dow Corning.RTM. DC1501 dimethiconol), neopentyl glycol
diheptanoate, PEG-8 laurate, isocetyl stearate, dimethicone
copolyol laurate, Dow Corning 2501 cosmetic wax (dimethicone
copolyol); isostearyl isostearate, isostearyl palmitate, isostearyl
alcohol, PPG-5-ceteth-20, PPG-10-cetyl ether, triethyl hexanoin,
ethyl hexyl isostearate, glyceryl oleate, and isopropyl
isostearate.
The emollient or emollient mixture or blend thereof incorporated in
compositions according to the present invention can,
illustratively, be included in amounts of 0.5-50%, preferably
1-25%, more preferably 3-5%, by weight, of the total weight of the
composition.
As described above, water is used to make the solution of
antiperspirant active and an additional amount of water may be
added as needed to adjust the refractive index. The total amount of
water from all sources may be present, for example in the range of
15-55%, particularly 40-55%. In a further optional aspect of the
invention, the water also may comprise up to 5% (based on the
entire composition) of an ionizable salt of the form M.sub.a
X.sub.b where a=1 or 2; b=1 or 2; M is a member selected from the
group consisting of Na.sup.+1, Li.sup.+1, K.sup.+1, Mg.sup.+2,
Ca.sup.+2, Sr.sup.+2, Sn.sup.+2, and Zn.sup.+2 ; and X is a member
selected from the group consisting of chloride, bromide, iodide,
citrate, gluconate, lactate, glycinate, glutamate, ascorbate,
aspartate, nitrate, phosphate, hydrogenphosphate,
dihydrogenphosphate, formate, malonate, maleate, succinate,
carbonate, bicarbonate, sulfate and hydrogensulfate. A salt of
particular utility is NaCl. As will be appreciated by those skilled
in the art, while it may be possible under certain circumstances to
add a salt directly to a portion of the mixture during
manufacturing, it is preferred to add the salt as a mixture or
solution of the salt in a carrier or solvent, particularly water.
Of course, various concentration of the salt can be made such as in
the range of 1-40%, particularly 10-30% and, more particularly,
25-30%.
The stability of the emulsions of the invention may be measured by
(1) visually evaluating the emulsions for phase separation and (2)
for gels, further monitoring the rheology using the viscosity tests
described below.
The compositions of the present invention can include other
optional ingredients to improve the aesthetics and/or performance
of the cosmetic compositions of the invention. These include
colorants, fillers, fragrances, emollients, masking agents, water
soluble emollients, hydrogen bonding modifiers (for example, urea,
guanidine hydrochloride, xylitol, trehalose, maltose and
glycerine), additional fragrances, additional preservatives, etc.
Such one or more other optional ingredients can be added to the
internal or external phases or both in appropriate amounts. For
example, fragrances will frequently be partitioned to both the
external and internal phases regardless of when or to what phase
(or final product) the fragrance is added.
In a preferred embodiment the refractive indices of the external
and internal phases are matched within 0.005 to obtain a clear
product.
The release of antiperspirant actives into the sweat is a
significant event in the development of an antiperspirant effect.
The magnitude of the antiperspirant effect is related to the
concentration of the antiperspirant salt in the sweat, and
therefore measuring the concentration of antiperspirant salt can
provide an estimate of antiperspirant efficacy. A variety of
methods can be used to evaluate antiperspirant salt concentration,
ranging from atomic absorption, ICP, and HPLC to solution
conductance of aqueous films. The later method is especially well
suited for measuring the release of small amounts of antiperspirant
salts. The methods outlined below use solution conductance to
estimate antiperspirant salt release upon short exposures to
deionized water.
As noted above, the conductance of the compositions of the
invention is defined with reference to a value of at least 250
micro Siemens/cm/ml when the composition is loaded with at least 7%
of an antiperspirant active (such as the antiperspirant actives
listed above) and when the conductance is measured by a fixed
geometry test. For purposes of clarification it should be explained
that there are a variety of tests and test conditions that can be
used to evaluate:
(1) "Conductance" is defined as an absolute measure of current flow
through a solution with the dimensions of micro Siemens/cm, which
value is independent of probe geometry. This value is divided by
the volume (in ml) of applied water to give the conductance number
with the units of micro Siemens/cm/ml. This test is deemed a more
reproducible measurement since it references a set of fixed
dimensions and units.
(2) Alternatively, "conductivity" as a measure of current flow
through a solution without reference to probe geometry, and which
is measured in micro Siemens. This test is convenient for quick
screening of solutions.
Standard Test for Thin Film Conductivity
One test for conductivity is called herein the "standard" test. A
non-conducting plastic block (for example, made from PLEXIGLAS.RTM.
material) to form an oval shaped well 12.2 cm.times.2.5 cm with a
depth of 100 microns. This depth corresponds to the mean thickness
of an antiperspirant product applied to the underarm of a human
person during real use conditions (approximately 50 to 100
microns). An aliquot of test sample is placed in the well of the
block sufficient to fill the well to the brim. Excess sample is
scraped off by running a flat edged instrument over the surface of
the block. The sample block, with the product film, is then either
(a) equilibrated at room temperature for two hours or (b) placed in
a synthetic underarm to simulate in vivo conditions. If method (b)
is used, the air temperature inside the synthetic underarm is
maintained at 33 to 35.degree. C. and a relative humidity of 85 to
95%, and the sample blocks are placed on a temperature controlled
surface maintained at body temperature (37.degree. C.). These
conditions closely approximate the temperature gradients normally
found in the underarm. Samples are equilibrated in either the (a)
or (b) environments for two hours prior to measurement of
antiperspirant salt release by solution conductivity. After two
hours the sample blocks are removed from the controlled environment
and placed on a stage for conductivity measurement. An aliquot of
250 microliters of water with a resistance of at least 17 mega ohms
is placed on the surface of the sample film, and the conductance of
the water is measured as a function of time with a Skicon 200 Skin
surface Hygrometer (I.B.S. Co., Ltd., Shizuoka-ken, 430, Japan)
using an Elsnau (MT-8C Probe) electrode (Todd Maibach &
Associates, San Francisco, Cailf.). The electrode is positioned so
that it touches the bottom of the test sample in the well.
Conductivity is measured in micro Siemens at 3.5 MHz. Data is
collected at 0.1 sec intervals for approximately 100 sec. Solution
conductivity after 10 seconds of exposure to the water is used to
compare the release of active salt for different formulations This
method is believed to be particularly useful for evaluating the
release of antiperspirant salts in the absence of other salts. The
standard method is useful as a quick screening tool for active salt
release studies. A solution conductivity of approximately 400 or
greater micro Siemens at 10 sec after application of the water
droplet to the surface of the test sample, can be considered
evidence of significant release of the antiperspirant active salt
from the film surface and correlates with improved antiperspirant
efficacy.
Fixed Geometry Test for Thin Film Conductance
One of the limitations of the Standard Test is that the area of the
water droplet is not controlled and, therefore, the apparent
conductance (which is measured as conductivity because the water
volume is not controlled) is dependent on droplet spreading. This
will lead to an underestimate of the actual solution conductance
(and therefore antiperspirant salt release), of water drops which
spread significantly. In order to measure the absolute
concentration of the antiperspirant salts the spreading of the
water drop must be stopped. This can be accomplished by placing a
well of know dimensions on the surface of the product film to
establish an area of constant size that is exposed to the water
droplet. A more predictable test is needed, such as the Fixed
Geometry Test.
The Fixed Geometry Test uses the same basic technique as the
Standard Test in terms of preparation of the test well, addition of
the test sample and equilibration of the sample to a selected
temperature. Instead of allowing the water to flow freely on the
surface of the test film, however, a second structure of
non-conducing plastic predrilled with holes of a fixed diameter is
clamped over the well block. The second structure with holes is
also made of a non-conducting material (such as PLEXIGLAS
material), is open on both ends and has an internal diameter of
1.905 cm. The bottom of each predrilled hole is fitted with a small
O-ring to prevent leakage of the water. A 400 microliter aliquot of
water (rather than the 250 microliter aliquot used in the Standard
Test) with a resistance of 17 mega Ohms is then placed in the hole
to cover the test sample. This will normally result in a liquid
height for water of about 1.4 mm. The Elsnau probe is positioned
through the drilled hole so that the bottom of the probe rests on
the bottom of the well at a right angle. Because of the fixed
shape, data can be obtained as conductance in micro Siemens/cm/ml
using the method described for calculation.
As will be appreciated by those skilled in the art, a variety of
other shapes, sizes and orientations of electrodes can be used. In
another variation on the Fixed Geometry Test, thin gold wires (99%
purity, set of 2, each about 1 mm in diameter) can be constructed
to be in parallel with the surface of the water (and covered by the
water) and conductance can be measured.
The electrode used in both types of tests must be calibrated so
that a conductivity in micro Siemens can be obtained. Such
calibration with a salt solutions in water of known conductance is
known to those skilled in the art.
While different readings can be obtained depending on the thickness
of the films, the test used, etc. it is important to establish a
standard test for purposes of defining conductivity according to
this invention. The Fixed Geometry Test is set as the defining test
because it is believed to be more reproducible. Thus a minimum
conductance value of 250 micro Siemens/cm/ml is the lower limit.
Interestingly, minimum values for the Standard Test seemed to run
about 400 micro Siemens due to the way the test was conducted. For
the data described here, samples should be placed in a chamber at
the humidity and elevated temperature conditions described above
for about 2 hours. Samples not subjected to elevated temperatures
should give higher values.
An average efficacy gel having a water content of greater than 35%
(such as Gillette's Right Guard Antiperspirant Gel) was compared
with an improved gel made according to Example 12 below. The
average efficacy gel has a standard conductivity of 295.+-.35 micro
Siemens at 10 seconds and a fixed geometry conductivity of
121.+-.47 micro Siemens/cm/ml at 10 seconds. The improved
formulation made according to this invention had a standard
conductivity of 4526 micro Siemens at 10 seconds. The improved
formulation was ranked as above average in efficacy in a forearm
test whereas the average gel was ranked as average in efficacy in a
clinical test.
While it is not known precisely how the compositions of this
invention work, it has been observed that they have a combination
of two important properties. These compositions exhibit superior
stability on the shelf and yet degrade on contact with the skin to
release the active ingredient with a higher level of efficacy than
is usually achieved. The deodorant and/or antiperspirant
compositions disclosed in this invention form metastable emulsions
when deposited on the skin. The decomposition of these emulsions
upon application can be assessed by the thin film conductance
method described herein.
Particular formulations of interest include:
Formulation A:
0.5-2.5% dimethicone copolyol (for example, Dow Corning 2-5185C
(48%))
55-65% elastomer in cyclomethicone (for example, KSG-15 from
Shin-Etsu)
1-10% PPG-3 myristyl ether
10-25% antiperspirant active (for example, Westchlor Zr 35 BX3 or
Summit AZG-368)
10-25% water
0.5-1.5% fragrance
Formulation B
1.0-3.0% dimethicone copolyol (for example, Dow Corning 2-5185C
(48%))
40-60% elastomer in cyclomethicone (for example, KSG-15 from
Shin-Etsu)
1-5% cyclomethicone (in addition to that found in the
elastomer)
4-12% PPG-3 myristyl ether
15-30% antiperspirant active (for example, Westchlor Zr 35 BX3 or
Summit AZG-368)
15-35% water
0.5-1.5% fragrance
Formulation C
1.0-3.0% dimethicone copolyol (for example, Dow Coming 2-5185C
(48%))
1-10% hydrogenated polyisobutene (for example, Fancol.TM. Polyiso
250)
40-55% elastomer in cyclomethicone (for example, KSG-15 from
Shin-Etsu)
3-8% PPG-3 myristyl ether
15-20% antiperspirant active (for example, Westchlor Zr 35 BX3 or
Summit AZG-368)
20-30% water
1.0-3.0% fragrance
Formulation D
1.0-3.0% dimethicone copolyol (for example, Dow Corning 2-5185C
(48%))
40-60% elastomer in cyclomethicone (for example, KSG-15 from
Shin-Etsu)
3-8% PPG-3 myristyl ether
15-30% antiperspirant active (for example, Westchlor Zr 35 BX3 or
Summit AZG-368)
15-30% water
0.5-1.5% fragrance
1-10% diethylhexyl naphthalate
Formulation E
0.5-2.5% dimethicone copolyol (for example, Dow Corning 2-5185C
(48%))
60-70% elastomer in cyclomethicone (for example, KSG-15 from
Shin-Etsu)
7-10% antiperspirant active (for example, Westchlor Zr 35 BX3 or
Summit AZG-368)
25-35% water
1-10% methylpropylene diol (MPDiol)
0.5-1.5% fragrance
Formulation F
1.0-3.0% dimethicone copolyol (for example, Dow Coming 2-5185C
(48%))
6-10% hydrogenated polyisobutene (for example, Fancol.TM. Polyiso
250)
35-45% elastomer in cyclomethicone (for example, KSG-15 from
Shin-Etsu)
6-10% PPG-3 myristyl ether
40-50% antiperspirant active as 43% active in water (for example,
active is Westchlor Zr 35 BX3 or Summit AZG-368)
no additional water
0.5-1.0% fragrance
Formulation G
0.1-0.6% dimethicone copolyol (for example, Dow Corning 2-5185C
(48%))
4-7% hydrogenated polyisobutene (for example, Fancol.TM. Polyiso
250)
40-50% elastomer in cyclomethicone (for example, KSG-15 from
Shin-Etsu)
4-7% PPG-3 myristyl ether
40-50% antiperspirant active as 43% active in water (for example,
active is Westchlor Zr 35 BX3 or Summit AZG-368)
no additional water
0.5-1.0% fragrance
Formulation H
0.5-2.0% dimethicone copolyol (for example, Dow Corning 2-5185C
(48%))
1-7% hydrogenated polyisobutene (for example, Fancol.TM. Polyiso
250)
40-50% elastomer in cyclomethicone (for example, KSG-15 from
Shin-Etsu)
45-55% antiperspirant active as 43% active in water (for example,
active is Westchlor Zr 35 BX3 or Summit AZG-368)
no additional water
0.5-1.5% fragrance
Formulation I
2-7% dimethicone copolyol (for example, Dow Corning 2-5185C
(48%))
0.1-1% Oleath-20
1-5% C12-15 alkyl benzoate (Finsolv TN)
15-40% elastomer in cyclomethicone (for example, KSG-15 from
Shin-Etsu)
15-25% antiperspirant active (for example, active is Westchlor Zr
35 BX3 or Summit AZG-368)
15-30% water
0.5-1.5% fragrance
The cosmetic composition according to the present invention can be
packaged in conventional containers, using conventional techniques.
Where a gel, cream or soft-solid cosmetic composition is produced,
the composition can be introduced into a dispensing package (for
example, conventional packages for gels with glide on applicators,
jars where the gel or cream is applied by hand, and newer style
packages having a top surface with pores) as conventionally done in
the art. Thereafter, the product can be dispensed from the
dispensing package as conventionally done in the art, to deposit
the active material, for example, on the skin. For roll-ons the
compositions can be placed in a conventional type of container.
This provides good deposition of the active material on the
skin.
Compositions of the present invention can be formulated as clear,
translucent or opaque products, although clear products are
preferred. A desired feature of the present invention is that a
clear, or transparent, cosmetic composition, (for example, a clear
or transparent deodorant or antiperspirant composition) can be
provided. The term clear or transparent according to the present
invention is intended to connote its usual dictionary definition;
thus, a clear liquid or gel antiperspirant composition of the
present invention allows ready viewing of objects behind it. By
contrast, a translucent composition, although allowing light to
pass through, causes the light to be scattered so that it will be
impossible to see clearly objects behind the translucent
composition. An opaque composition does not allow light to pass
therethrough. Within the context of the present invention, a gel or
stick is deemed to be transparent or clear if the maximum
transmittance of light of any wavelength in the range 400-800 nm
through a sample 1 cm thick is at least 35%, preferably at least
50%. The gel or liquid is deemed translucent if the maximum
transmittance of such light through the sample is between 2% and
less than 35%. A gel or liquid is deemed opaque if the maximum
transmittance of light is less than 2%. The transmittance can be
measured by placing a sample of the aforementioned thickness into a
light beam of a spectrophotometer whose working range includes the
visible spectrum, such as a Bausch & Lomb Spectronic 88
Spectrophotometer. As to this definition of clear, see European
Patent Application Publication No. 291,334 A2. Thus, according to
the present invention, there are differences between transparent
(clear), translucent and opaque compositions.
Compositions of the present invention may be made by the techniques
described in the Examples below. In general, the external and
internal phases are formed separately using heating with the
addition of a non-ionic emulsifier as needed. The alcohol component
is added to the internal phase. The internal phase is added to the
external phase very slowly. After the addition has been completed,
the mixture is stirred at speeds on the order of 250-1000 rpm (for
example, 700 rpm), to achieve a homogeneous mixture, followed by
homogenization at speeds which are correlated with a voltage
setting of about 55-65, particularly 60, on a Powerstat Variable
Autotransformer to achieve the target viscosity. Compositions with
a viscosity of 0-50,000 centipoise, especially 5,000-20,000
centipoise, may be suitable for roll-on products while compositions
having a viscosity on the order of 50-400,000 centipoise may be
more suitable for soft solids or creams.
A variety of equipment and techniques may be used to obtain the
compositions of the invention, including one pass homogenization,
colloidal mill. Examples of such equipment include Sonic Production
Sonolator 200-30, and Sonic Tri-Homo Colloid Mill both of which may
be obtained from Sonic Corporation, Stratford, Conn.
It is believed that the more homogeneous the composition is and the
more uniform the particle size, the better properties of the
composition.
Throughout the present specification, where compositions are
described as including or comprising specific components or
materials, or where methods are described as including or
comprising specific steps, it is contemplated by the inventors that
the compositions of the present invention also consist essentially
of, or consist of, the recited components or materials, and also
consist essentially of, or consist of, the recited steps.
Accordingly, throughout the present disclosure any described
composition of the present invention can consist essentially of, or
consist of, the recited components or materials, and any described
method of the present invention can consist essentially of, or
consist of, the recited steps.
EXAMPLES
The following Examples are offered as illustrative of the invention
and are not to be construed as limitations thereon. In the Examples
and elsewhere in the description of the invention, chemical symbols
and terminology have their usual and customary meanings. In the
Examples as elsewhere in this application values for n, m, etc. in
formulas, molecular weights and degree of ethoxylation or
propoxylation are averages. Temperatures are in degrees C unless
otherwise indicated. If alcohol is used, it is 95% unless otherwise
indicated. Unless otherwise indicated, "water" or "D.I. water" mean
deionized water. As is true throughout the application, the amounts
of the components are in weight percents based on the standard
described; if no other standard is described then the total weight
of the composition is to be inferred. Various names of chemical
components include those listed in the CTFA International Cosmetic
Ingredient Dictionary (Cosmetics, Toiletry and Fragrance
Association, Inc., 7th ed. 1997). Viscosities are measured using
Brookfield viscometers unless otherwise indicated. While specific
amounts of particular elastomers have been described, there are
chemical differences in the variety of elastomers that are
available. The use of different elastomers may result in the need
to increase or decrease the amount of elastomer used in a
particular formulation, especially if a clear product is
desired.
Example 1: General Method
In general, the external and internal phases are formed separately
either at room temperature or with heating as described below. The
internal phase is added to the external phase very slowly while
stirring at to form an emulsion. After the addition has been
completed, the mixture is stirred at higher speed to achieve a
homogeneous mixture. The final formula viscosity is then achieved
by homogenizing the emulsion under either batch or continuous
process conditions as described below. The fragrance may be added
at any time during the process prior to final homogenization.
Preparation of the External Phase:
The ingredients to be used in the external phase (including the
elastomer) are weighed out at room temperature and combined in a
suitable vessel such as a 2 liter glass beaker. The mixture is
stirred at about 500 rpm for 15-20 minutes using an overhead mixer
such as a Lightnin Mixer Model L1003. If a waxy or solid emollient
is to be added to the external (also called "continuous") phase,
the mixture may be heated to facilitate dissolution while stirring
then cooled to room temperature prior to combination with the
internal phase as described below. The elastomer component is
obtained as a suspension of elastomer in cyclomethicone (for
example at a concentration of 6% active in D5 cyclomethicone). The
elastomer component is added to the external phase with stirring at
high speed (500-700 rpm for a 0.5 kilogram batch) until no
particles of elastomer are visible to the eye.
Preparation of the Internal Phase:
The internal dispersed phase is prepared as described below.
Ingredients are mixed for a time sufficient to achieve homogeneity.
The antiperspirant active used (for example, Westchlor Zr 35 BX3
(for example, 43% aluminum-zirconium glycinate in water) is weighed
into a large beaker equipped with an overhead stirrer. Other
internal phase ingredients are then added while stirring.
The fragrance (if any is used) is added last and may be added to
the external phase normally (although it may be added to either the
external phase or the internal phase if alcohol is used in the
formulation) or the final formula prior to homogenization. For many
of the examples described here, one could add the fragrance to the
external phase.
If an optional non-ionic emulsifier such as Oleath-20 is used, the
emulsifier and propylene glycol are combined in a separate beaker
and heated to 40 degrees C with stirring until the non-ionic
emulsifier completely dissolved. The heat is turned off and the
remaining ingredients to be used in the internal phase, including
the antiperspirant active are weighed out and added to the mixture
of propylene glycol and non-ionic emulsifier.
If water or a salt solution are used, the internal phase is
prepared as follows. The solution containing antiperspirant active
salt as received from supplier is weighed into a large beaker
equipped with a magnetic stirrer. Additional ingredients such as
propylene glycol, ethanol and water are added while stirring. If a
salt water solution is used (such as for NaCl, etc.), the salt
water solution is prepared by dissolving the crystalline salt in
water in a separate beaker and stirring until dissolved. The salt
water solution is then added to the rest of the internal phase and
the mixture is stirred until homogeneous.
Preparation of the Emulsion:
The internal phase made as described above is then added to the
external phase over the course of 15-30 minutes while stirring at a
speed of 500-700 rpm. After the addition is complete, the mixture
is stirred at 500-700 rpm for 20 minutes using a Lightnin Mixer
Model L1003. The mixture is then homogenized for 2-4 minutes
(especially 3 minutes) using a homogenizer from Greerco Corp.,
Hudson, N.H. at a reading of about 60 on a Powerstat Variable
Autotransformer from Superior Electric Co., Bristol, Conn.
Further Processing:
The product is then further processed by homogenization to achieve
the desired final viscosity. This can be done by using a
Gilford-Wood Model 1-L (Greerco Corp., Hudson, N.H.) homogenizer.
The homogenizer speed is controlled by a Powerstat Variable
Autotransformer Type 3PN116B (Superior Electronic. Co., Bristol,
Conn.). Typical voltage setting and processing time are chosen to
give a desired final formula viscosity.
An other method of homogenization of the final product is to pass
the emulsion through a colloid mill such as a Sonic Tri-Homo
Colloid Mill or a process sonolator such Sonic Production Sonolator
200-30 both available from Sonic Corporation of Stratford, Conn.
Process conditions are chosen to give the desired final product
viscosity.
Example 2: Evaluation of Viscosity
Brookfield Viscosity
Viscosity can be measured using a Brookfield instrument (Model
DV11+) with an E Spindle at 2.5 revolutions per minute (rpm) and a
setting of S 95. Units are in centipoise ("cps").
Carri-Med Viscosity
A second way of evaluating rheology is with the use of Carri-Med
equipment to obtain complex viscosity. Rheological parameters can
be measured using a Carri-Med CSL 100 instrument with parallel
plates. Initially the zero gap is set on the instrument. A sample
of approximately 5 grams is placed on the stage of the instrument.
A 15 minute compression is used for sample equilibration. The
excess of the sample is scraped around the plate geometry. The
Theological parameters G, G", tan (delta) and complex viscosity
(n*) can be measured by torque sweep experiments. An acrylic plate
6 cm in diameter can be used. A gap (1000 microns) is used between
the two plates (acrylic plates 6 cm in diameter). Temperature is
maintained at 23 degrees C. The oscillation stress can be varied
from 2.358 Pa to 50.74 Pa with an oscillation frequency kept
constant at 1 Hertz. Units are in Pascal seconds ("Pa sec").
Examples 3-12 Compositions
The method described in Example 1 was used to make the compositions
listed in Table A with the types and amounts of ingredients listed
in the Table. Amounts are in percent by weight based on the total
weight of the composition.
TABLE A Ingredient Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7 Ex. 8 Ex. 9 Ex. 10
Ex. 11 Ex. 12 External Phase Elastomer (KSG-15, 6% active) 62 50 48
40 41.5 42.0 46.5 35 32.17 25 Dimethicone copolyol 2 2 1.5 4 1.5
0.5 1.0 1.0 2.48 1.0 (Dow Corning 2-5185, 48% active in
cyclomethicone) Hydrogenated polyisobutene 0 0 5 8 5 5 5 5 4.95 0
(Polyiso 250) PPG-3 Myristyl Ether 5 5 4.5 0 4.5 5.0 0 0 0 5 C12-15
alkyl benzoate 2.0 (FINSOLV TN) Cyclomethicone 0 2 0 0 0 0 0 0 0 0
(Dow Corning 245) Fragrance 1 1 1 1 1 1 1 1 1 1 Internal Phase
Antiperspirant Active.sup.a 15 20 17.5 19.5 46.5 46.5 46.5 58 59.40
48.45 Water (deionized).sup.b 15 20 22.5 25 0 0 0 0 0 0 Oleath-20
(HLB > 8) 0 0 0 0.5 0 0 0 0 0 19.55 Total 100 100 100 100 100
100 100 100 100 100 .sup.a = Westchlor Zr 35 BX3 (77% solid active
on anhydrous basis) dissolved in water was used for Examples 3, 4,
5 and 6. Westchlor Zr 35 BX3 (33.55% actives on an anhydrous basis
with water) was used for Examples 7, 8, 9 and 10. Summit AZG 368
(32% actives on an anhydrous basis in water) was used for Example
11. An active as prepared by Example 13 (41.28% solids on an
anhydrous basis dissolved in water) was used for Example 12. .sup.b
= Note that in the examples, sometimes the antiperspirant active is
listed as a solution (which will include a water component) under
the "active" designation with little or no water and sometimes the
active and water are listed separately.
TABLE B Property Ex. 3 Ex. 4 Ex. 5 Ex. 7 Ex. 8 Ex. 9 Ex. 10 Ex. 11
Ex. 12 Initial Brookfield 160,000 190,000 200,000 200,000 110,000
230,000 290,000 420,000 250,000 Viscosity (centipoise) Brookfield
Viscosity 150,000 190,000 170,000 190,000 95,000 -- 200,000 --
248,000 after 4 weeks at 49.degree. C. (centipoise) Initial
Carri-Med 94 134 154 196 146 198 183 313 229 Complex Viscosity
(Pascal seconds) Carri-Med Complex Viscosity 88 141 109 159 -- 160
-- 328 -- (Pascal seconds) after 4 weeks at 49.degree. C.
Examples 3-12: Viscosity
The viscosity of Examples 3-7 was evaluated using the method of
Example 2 to obtain viscosity data from the Brookfield method and
rheology data from the Carri-Med method. The data is shown in Table
B.
Examples 3-12: Conductivity
The Standard Method described above was used with a 250 microliter
drop of water placed on a 100 micron thick film of the test
formula. Before the test each sample was equilibrated for 2 hours
at 35 degrees C and 85% relative humidity (simulation of underarm
conditions). Since the Fixed Geometry Method was not used to obtain
conductance data, for the listed Examples, the diameter of the
spreading of the water drop is given. As noted above a minimum of
250 micro Siemens for the Fixed Geometry Method is the defined
lower limit. Readings for conductivity using the Standard Method
will be somewhat higher. The Control Gel Example was prepared using
the same procedure as described for Examples 3-12 with 5%
dimethicone copolyol (Dow Corning 2-5185 diluted to 40%); 1%
Cyclomethicone (DC 245 (D5)); 53.37% antiperspirant active (28% in
propylene glycol) (Westchlor 4105); 6.08% propylene glycol; 9.12%
alcohol (SDA 40 200); 1.0% fragrance; 0.23% Tween 80; and 8.5%
elastomer (5.8% actives in D5 cyclomethicone--elastomer described
in U.S. Pat. No. 6,060,546). The Control Stick Example was Lady
Speed Stick. The data shows that emulsion of the invention has
conductivity as good as or better than the stick.
The samples were prepared by matching the RI's of the two phases
(within 0.005) and samples were visually observed to be clear.
Conductivity was evaluated using the Standard Method. The results
are listed in TABLE C.
TABLE C Property Ex. 3 Ex. 4 Ex. 5 Ex. 7 Ex. 8 Ex. 10 Ex. 12
Conductivity at 100 seconds 584 3327 3325 4156 2776 4436 5305
(micro Siemens) Diameter of water droplet 1.77 3.3 4.27 3.6 2.6
3.24 5.03 after spreading (cm) Conductivity at 10 seconds 250 2656
2691 3224 154 4071 4526 (micro Siemens) % oil phase 70 60 60 54 54
42 30
The data in Table C may be compared with the data in Table D which
is data for controls. Control stick #1 is Lady Speed Stick.RTM.
antiperspirant (Mennen), and Control gel #2 is Right Guard.RTM.
antiperspirant (Gillette). Normally a gel product does not have
very good conductivity while stick products have much better
conductivity. The data in Table C shows that compositions of the
present invention have conductivity values comparable to stick
products.
TABLE D Control Control Stick Control Property Gel #1 #1 Gel #2
Conductivity at 100 seconds 180 3077 (micro Siemens) Diameter of
water droplet after 0.87 1.7 1.2 spreading(cm) Conductivity at 10
seconds 154 1627 295 (micro Siemens) % oil phase 30 (suspension)
20
Examples 6 and 6A: Comparison
By way of a comparative product, the composition described in
Example 6 was repeated to make a composition of Example 6A with the
following amounts of ingredients: 50% elastomer; 2% dimethicone
copolyol; 5% hydrogenated polyisobutene; 2% cyclomethicone; 1%
fragrance; 20% active (Westchlor Zr 35 BDM CP-5(77% solids); 15%
water; and 5% Oleath-20. The product obtained was not clear.
Examples 13-15: Experimental Antiperspirant Salts
Improved aluminum zirconium tetrachlorohydrex gly salt can be made
using the following Examples 13-15. The goal is to enhance the
smallest Al species (Peak-5) by lowering the metal:chloride molar
ratio of the tetra-salt to be in the range of 1.2-0.9:1 and to
stabilize the Zr polymeric species by raising the glycine/Zr molar
ratio to be greater than 1.4:1.
Example 13
Glycine powder (159 g) is added to a zirconium compound (1000 g of
a 31 % solution of zirconium oxychloride (ZrOCl.sub.2)) with
stirring. Aluminum chlorohydrate ("ACH") (1120 g of a 50% aqueous
ACH solution) is then added with additional stirring. The final
solution is then diluted with distilled water into an anhydrous
concentration of 33.0%, with a glycineizirconium molar ratio of
1.45:1; aluminum/zirconium molar ratio of 3.56:1, and
metal/chloride ratio of 1.01:1.
Example 14
Glycine powder (159 g) is added to a zirconium compound (1000 g of
a 31% solution of zirconium oxychloride (ZrOCl.sub.2) with
stirring. ACH (1204 g of a 50% aqueous ACH solution) is then added
with additional stirring. The final solution is then diluted with
distilled water into an anhydrous concentration of 30.0% with a
glycine/zirconium molar ratio as 1.45:1; an aluminum/zirconium
molar ratio of 3.82:1, and a metal/chloride ratio of 0.98.
Example 15
A solution of AlCl.sub.3 (200g of 28% aqueous solution) is added to
a ZAG solution (800 g of a 43% solution of Westchlor Zr 35BX3) with
stirring. The mixture is then diluted into an anhydrous
concentration of 30%. The final solution has an aluminum/zirconium
molar ratio of 4.36:1; a metal/chloride ratio of 0.94:1; and a
glycine/zirconium ratio of 0.97:1.
Analytical Data for Examples 13-15
Size exclusion chromatography ("SEC") or gel permeation
chromatography ("GPC") are methods frequently used for obtaining
information on polymer distribution in antiperspirant salt
solutions. With appropriate chromatographic columns, at least five
distinctive groups of polymer species can be detected in a ZAG,
appearing in a chromatogram as peaks 1, 2, 3, 4 and a peak known as
"5,6". Peak 1 is the larger Zr species (greater than 120-125 A).
Peaks 2 and 3 are larger aluminum species. Peak 4 is smaller
aluminum species (aluminum oligomers) and has been correlated with
enhanced efficacy for both ACH and ZAG salts. Peak 5,6 is the
smallest aluminum species. The relative retention time ("Kd") for
each of these peaks varies depending on the experimental
conditions. Data for Table E was obtained by using the methods
described in our patent U.S. Pat. No. 5,997,850, incorporated by
reference herein as to the description of analytical techniques for
obtaining peak analyses.
TABLE E Polymer Distribution of the Improved Salts (SEC analysis)
Peak-1/ Peak-2/ Peak-4/ Peak-5/ Peak-3 Peak-3 Peak-3 Peak-3 Example
13 0 0.2 0.24 3.11 Example 14 0 0.03 0.17 1.71 Example 15 0.95 0.34
0.27 2.60 WZR35BX3.sup.a 0.55 0.24 0.18 0.55 .sup.a = commercial
salt from Westwood.
* * * * *